Ask question

Ask question

All categories

2 years ago

7

One number is six less than two times another. If their sum is increased by two, the result is fourteen. Find the numbers.

1 answer:

7nadin3 [17]2 years ago

5 0

Answer:

2x-6+2=14

Step-by-step explanation:

2x-6+2=14

2x-4=14

2x=14-4

2x=10

x=5

You might be interested in

The surface area of a cylinder is increasing at a rate of 9 pi square meters per hour. The height of the cylinder is fixed at 3

Alekssandra [29.7K]

Answer:

$9\pi \text{ cubic meters per hour}$

Step-by-step explanation:

Since, the surface area of a cylinder,

$A= 2\pi r^2 + 2\pi rh$ ................(1)

Where,

r = radius,

h = height,

If $A= 36\pi\text{ square meters}, h = 3\text{ meters}$

$36\pi = 2\pi r^2 + 2\pi r(3)$

$18 = r^2 + 3r$

$\implies r^2 + 3r - 18=0$

$r^2 + 6r - 3r - 18 = 0$ ( by middle term splitting )

$r(r+6)-3(r+6)=0$

$(r-3)(r+6)=0$

By zero product property,

r = 3 or r = - 6 ( not possible )

Thus, radius, r = 3 meters,

Now, differentiating equation (1) with respect to t ( time ),

$\frac{dA}{dt}= 4\pi r\frac{dr}{dt} +2\pi(r\frac{dh}{dt} + h\frac{dr}{dt})$

∵ h = constant, ⇒ dh/dt = 0,

$\frac{dA}{dt} = 4\pi r \frac{dr}{dt} +2\pi h \frac{dr}{dt}$

We have, $\frac{dA}{dt}=9\pi\text{ square meters per hour}, r = h = 3\text{ meters}$

$9\pi = 4\pi (3) \frac{dr}{dt}+2\pi (3)\frac{dr}{dt}$

$9\pi = (12\pi + 6\pi )\frac{dr}{dt}$

$9\pi = 18\pi \frac{dr}{dt}$

$\implies \frac{dr}{dt} =\frac{1}{2}\text{ meter per hour}$

Now,

Volume of a cylinder,

$V=\pi r^2 h$

Differentiating w. r. t. t,

$\frac{dV}{dt}=\pi ( r^2 \frac{dh}{dt}+h(2r)\frac{dr}{dt})=\pi ((3)(6) (\frac{1}{2})) = 9\pi \text{ cubic meters per hour}$

6 0

2 years ago

What is the missing number<br> 7 x ( ? x 9) = 63

GrogVix [38]

The ? is 1.

7*(9*1)=63

Hope this helps!!

6 0

3 years ago

Factor the question: 4x+8y+16

kirill [66]

Y= - X/2 = 2 this is the answer

8 0

2 years ago

Holly missed 6 of 181 school days this year. Approximately what percent of school days was Holly in attendance?

Natasha2012 [34]

$181-6=175\\\\\frac{175}{181}\cdot100\%=\\\\\frac{17500}{181}\%=\\\\96.7\%\approx97\%\\\\Answer\ C$

4 0

3 years ago

Two quantities, x and y, are directly proportional. If x is doubled, what happens to y?

vagabundo [1.1K]

Answer:

y is also doubled.

Step-by-step explanation:

Direct proportionality between $x$ and $y$ means that

$y \propto x$

or

$y=cx$ ,

which indicates a linear relationship between $x$ and $y$ because they are related by a constant.

Therefore, if x is doubled, then the new value of $y$ is $y_{new}$

$y_{new}=c(2x)$

$y_{new}=2(cx)$

$y_{new}=2y$

The new value of $y$ is 2 times the previous; therefore, $y$ is doubled as $x$ is doubled.

7 0

3 years ago

Read 2 more answers